Automatic starting mechanism



A ril 2, 1935.

D. L. W E RTZ ET AL AuToMATIc STARTING MECHANISM Filed Feb. 24, 1931 m w T n M m V T Tmm P m T Z .w nmw w BF Patented Apr. 2, 1935 UNITED STATES AUTOMATIC .STARTIN G MECHANISM Daniel L. Wertz and Frank '1. chi-nasa Elmira, N. Y., assignors to Eclipse Machine Company,

, N. Y., a corporation of New York .1

Application February 24, 1931, Serial No. 518,011

6 Claims.

This invention relates to automatic starting mechanism and more particularly to a device for protecting the starting mechanism incase of sustained electrical overloading such as would be 5 caused for instance by an attempt to start a motor vehicle with the transmission gears engaged and the brakes set, or by jamming of the starter gearing due to failure to secure proper mesh thereof.

In automatic starting mechanism of the type in which closure of a manual switch such as the ignition switch of the engine causes automatic operation of the starting mechanism until the engine becomes self-operative, failure of the 15 engine to start by reason of overloading or jamming of the starter gearing causes the starting circuit to remain closed whereby the starting motor may become overheated and the battery charge will become rapidly depleted.

It is an object of the present invention to provide an automatic starting mechanism embodying a novel means for opening the starting circuit in case the starting motor is stalled for any reason.

Another object of the invention is the provlsion of such a device in which the starting circuit is opened alter a predetermined heating of the parts due to electrical overload.

A further object is to provide such a device in 30 which the heating eiIect of certain elements of the starting circuit is used to open a control circuit for the starting switch.

Another object is to provide such a device which involves the use of no additional electrical con- 35 tacts or control elements to accomplish the overload release function.

Further objects and advantages will be apparent to those skilled in the art from the following description taken in connection with the i accompanying drawing in which:

Fig. 1 is a semi-diagrammatic illustration of a preferred embodiment of the invention, the automatic starting switch elements being shown in elevation and partly in section; and

Fig. 2 is a section taken substantially on the line 2-4 of Fig; 1.

In Fig. 1 there is illustrated a starting motor circuit including a battery III, one terminal oi. which is grounded as at I l and the other terminal 50 of which is connected by a lead I! to an automatic starting switch comprising stationary elements l3 and I4 and the insulated bridging element It. The stationary switch element or conductor I4 is connected through a single turn coil i5 i1 and lead II to the starting motor SM which is grounded at I 9 and is adapted when energized to crank an internal combustion engine not illustrated. The single turn coil I1 is provided with an adjustable magnetic core 20 surrounded by a spacing sleeve 30.

The switch element It is mounted on the movable magnetic plunger Zl which is normally maintained in its upper position by means such as a spring I 5, but which may be drawn down to close the starting switch by a solenoid 22. Said solenoid is included in a control circuit comprising battery I0, lead 1!, manual switch 23, lead 24, lead 25, contacts 26 and 21, spring metal strip 29 and ground connection 28. Spring strip 29 carries the movable contact 21 and normally holds the same against the stationary contact 26 whereby closure of the manual switch 23 by the operator will cause the energization of solehold 22 to close the starting switch and energize the starting motor. Manual switch 23 is preferably arranged to control the ignition circuit of the engine as indicated, so that closure of said switch will simultaneously close the ignition circuit and operate the automatic starting mechamsm.

Means are provided for automatically opening the control circuit when they engine starts, for holding said circuit open as long as the engine is self-operative, and for delaying the closing thereof until apredetermined time after the engine has come substantially to rest. As illustrated, these means include a wedge-shaped weight member 3| mounted in the end of the spring strip 28 in the path of movement of a roller 32. Said roller is mounted on the end of a lever 33 pivoted at 34 and having a pin 35 at an intermediate point 'thereol' projecting laterally between a pair of flanges 36 and 31 on a movable magnetic relay plunger 38. A voltage coil 39 and a generator coil 4| are arranged to surround the lower part of relay plunger 38 and when energized, attract it downwardly. The voltage coil 39 is connected at one end by a lead 42 to the stationary switch member [4 and is grounded at its other end as indicated at 43. Generator coil II is connected at one end by a lead 44 to the generator G and is also grounded at its other end at 43. Plunger 33 is normally retained in its upper position against the spacing sleeve by a spring 46 whereby the lever 33 is maintained as shown in Fig. 1 out of contact with the weight member 3| so that contacts 26 and 21 are normally closed.

In the operation of the device so far described, closure of the ignition switch 23 completes the stantially to rest.

control circuit from the battery I!) through lead I12, switch 23, lead 24, coil 22, lead 25, contacts 26 and 21, spring strip 29 and ground connection 28. The consequent energization of coil 22 causes switch plunger 2| to move the starting switch member l6 into contact with switch members I3 and I4 thus completing the starting circuit from battery Ill through lead |2, starting switch |3, I6, 14, single turn coil |1, lead l8, starting motor SM and ground connection |9 whereby the starting motor is caused to crank the engine. During this time, the voltage coil 39 is energized by reason of its connection to the starting switch member I4, but the heavy current traversing the single turn coil |1 magnetizes the adjustable core 20 therein sufficiently to hold the plunger 38 in its upper position.

When the engine starts, the load on the starting motor is relieved, and the consequent reduction of the current through the single turn coil I1 together with the increase of voltage drop through the voltage coil 39 enables the latter to overcome the effect of the single turn coil H and draw the plunger 38 downward, causing the lever 33 to.

carry the roller 32 into engagement with the weight member 3| and bend the spring strip 29 backward sufiiciently to break the contacts 26, 21. The consequent opening of the control circuit causes the release of the switch plunger 2| whereby the spring I operates to open the starting switch. The relay plunger 38 is not immediately released, however, since the voltage coil 39 is traversed by a slight amount of current generated by the starting motor spinning by momentum in its residual field, this current being suificient to hold the plunger 38 against its pole piece 48 until the starting motor has come sub- Before the voltage coil 39 becomes entirely deenergized, the generator G which is driven from the engine builds up sufficient voltage to energize the generator coil 4| and retain the relay plunger 38 in its lower position,

thus holding open the contacts 21, 26 as long as the engine is self-operative.

If the engine should stall for any reason, the coil 4| becomes deenergized and the spring 46 raises the relay plunger 38, releasing the weight member 3| which vibrates for a predetermined length of time due to its pendular mounting, on the spring strip 29, thus giving the engine time to come completely to rest.- When the vibration ceases and the contact 21 comes to rest against the contact 26, the starting operation is repeated.

If during the starting operation, the starting motor is stalled for any reason so that it is unable to crank the engine, a very heavy fiow of current traverses the starting circuit since it is not opposed by a counter electro-motive force built up in the starting motor. This causes the elements of the starting circuit to become heated, this heating effect being particularly noticeable in the elements of the starting switch and in the armature of the starting motor. In order to protect these elements from overheating and in order to prevent unnecessary drains on the starting battery, means have been provided according to the present invention to cause the starting switch to be opened in response to a predetermined rise in temperature of the elements of the starting circuit.

In the form of the invention herein illustrated this is accomplished through the instrumentality of a heat-responsive element in the form of a bi-metallic strip 41 mounted at one end on an element of the starting switch such as the stationary conductor I4, and thermally connected thereto. The free end of said bi-metallic strip is adapted to bend to the right in Fig. 1 when the temperature thereof is raised, and is connected to a strip 48 of insulating material in any suitable way as by entering a notch 49 in the end thereof. The other end of the insulating strip 48 is connected to an intermediate point of a lever 5| (Fig. 2) which is mounted at one end on a fixed pivot 52 and the other end 53 of which is normally adjacent the spring strip 29 as illustrated. It will be seen that the connection so formed between the heat-responsive element .41 and the spring strip 29 is such that movement of the free end of the heat-responsive element to the right in Fig. 1 is transmitted to the spring strip 29 to move the contact 21 away from contact 26, thus breaking the control circuit.

In operation, if the starting circuit is closed in the manner above described, and the starting motor should be stalled for any reason, the switch element I4 will become heated and will transmit this heat to the bi-metallic element 41 causing the free end of the same to move to the right in Fig. l. Contact 21 is thus moved away from the fixed contact 26, breaking the control circuit and releasing the starting switch plunger 2|. When the parts cool down sufiiciently to allow the contact 21 to again close the control circuit, the starting operation will be repeated, and if the motor is still prevented from rotation, the releas ing operation will again take place. The opening and closing of the starting switch under these circumstances causes a clicking noise which serves to remind the operator to open the ignition circuit and take the necessary steps to free the or other electrical members and which may be economically produced and readily assembled within said starting mechanism.

Although but one form of the invention has been shown and described in detail, it will be understood that other embodiments are possible and that changes might be made in the proportions and arrangements of the parts without departing from the spirit of the invention as defined in the claims appended hereto.

. What is claimed is:' 1

1. Automatic starting mechanism for internal combustion engines including a starting motor circuit embodying a switch having a conducting element which is heated by the passage of starting current therethrough, and means including a heat responsive element mounted on said conductor and thermally connected thereto for causing said switch to be opened in response to such a heating efiect of said conductor to a predetermined temperature.

2. Automatic starting mechanism for internal combustion engines including a starting switch, means for automatically opening said starter switch when the engine starts, and forclosing said switch if the engine stalls, manually operable controlling means for said first mentioned means and means including heat-responsive means thermally connected to an element of said switch for causing said switch to be opened at a predetermined temperature of said element.

3. Automatic starting mechanism for internal combustion engines, including a starting motor circuit, a control circuit for automatically closing said starting circuit in case the engine-stalls, means for delaying the closing of the starting circuit until a predetermined time after the engine comes substantially to rest, and means operating on said delaying means for causing the starting circuit to be opened in load on said starting circuit; 4. Automatic starting mechanism for internal combustion engines including a starting motor circuit, a control circuit for automatically closing said starting circuit in case the engine stalls, means for delaying the closing of the starting circuit until a predetermined time after the engine comes substantially to rest, and heat-responsive means operating on said delaying means for causing the starting circuit to be opened in response to a predetermined rise in temperature within said starting circuit. 5. Automatic starting mechanism for internal case of an overcombustion engines including a starting motor circuit, a control circuit including a pair of contacts, closure of which causes the control circuit to close the starting circuit, means for holding open said contacts while the engine is self-operative, a conductor forming part of the starting circuit, and heat responsive means thermally connected thereto for opening said contacts in response toa predetermined rise in temperature of said conductor.

6. In an automatic starting mechanism for internal combustion engines, a starting motor circuit including an automatic switch, a control circuit for said switch including a ,pair of contacts, closure of which causes closure of the starting switch, means for holding open said contacts while the engine is self-operative, means for delaying closure of said contacts until a predetermined time after the engine has come substantially to rest, a heat-responsive element mounted on an element of said switch and thermally connected thereto, and connections between said heat-responsive element and said delaying means for opening said contacts upon a predetermined rise in temperature of said switch element.

DANIEL L. WERTZ. FRANK T. CHRISTIAN. 

